Can't tell the countries with a program!
Anyway, for reference here is a very complete list from another site of current restrictions in Europe and around the world. Of course, trust but verify before making life-changing decisions.
https://thepointsguy.com/guide/reopening-soon-a-country-by-country-guide-to-coronavirus-recovery/
These lists always make interesting reading, especially if you are tracking trends. But the first country I checked, the information was incorrect for the situation today (and for the last few weeks actually).
I find the following seems to be kept more up to date. I've read that this is the site the airlines use for reference:
Like James, I am really wary of places that claim to aggregate all that info, as it changes so frequently, and the details are so important and sometimes hard to get right. IATA, however, is literally the organization that HAS to get this right, as they keep all the airlines and government authorities informed, so that's where I would go if I weren't looking at a specific country's official website(s) (which I still think is the very best option).
(Also, I always imagine the people at commercial publications leaving this to a lackadaisical intern who kinda does his best but some days doesn't really check, or doesn’t really understand . . . that may be a very unfair assumption on my part, I realize !!!)
I just looked at 2 countries, the UK and Switzerland.
I'm sorry to say that the points guy link in the OP has significant errors in both.
